Recycling: Current Results
recyclingGallery of some 3d prints from recycled filament
Black and colour mix #
3D benchy, a benchmark for 3d printers. The black recycled PLA filament printed well. It also kept a black colour after being a mix of 40% black, 30% brown and 30% colourmix.
The two smaller benchies look brown, but the original granules were purely a colourmix. The colours were all mixed thoroughly together during melting.
The colour mix granules were wet during extrusion, but then I dried the resulting filament. They printed fine but some very slight extrusion irregularities can be felt on the surface.
The colourmix benchies also have slightly inconsistent colours along the filament length. This manifests as colour differences along slices of the models: e.g. a red tinge on the roof of the smallest one, most visible on the first picture.
Yellow #
During shredding, I very slightly mixed some purple PLA granules into the yellow PLA ones. Even though they are present in a small quantity, yellow is a light colour and purple overpowered it somewhat.
The resulting filament has a slight green tinge. Except for that, it prints excellently and has a very good diameter consistency.
The current diameter sensor I have is a 3d printed articulation that produces very noisy data. When manually checking with calipers, the diameter is more precise than what the sensor reports. But I cannot use that in an automated or continuous way.
Here the extrusion is very consistent, but there are some green stripes present because of the purple.
Then, a print-in-place toy engine benchmark. It challengingly tests bed adhesion with small surfaces, layer adhesion along the camshaft, single-line bridging extrustions and overhangs. It also presents a new technique, for printing the pistons fixed: printing over a single-line bridge.
https://www.printables.com/model/212989-print-in-place-engine-benchmark-the-bengine
This is a very challenging model to print, but the yellow recycled PLA did quite well. The print-in-place functionality is fully operational after applying a little force to break the single-line bridges just after printing, and the camshaft can rotate and push the pistons around.
Here is the camshaft in different positions, the pistons are also able to move in their full range of motion.
Conclusion #
The filament recycling process works well and produces satisfactory results.
I still need to find a better continuous diameter sensor, and something to make the shredding process more time-efficient.
Colour purity is also a difficult problem to solve, and I think that for now I can concentrate on darker colours or just making black.
This recycling project is supported by
